Portable elevating apparatus



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PORTABLE ELEVATING APPARATUS Filed May 8, 1924 3 Sheets-Sheet -3 Patented Apr. 19, 1927.

UNITED STATES PATET E FlQE.

BERGER STOCKFLETH, F BEERIEN SPRINGS, AND FREDERICK 1V. BURGER, OF N ILES,

MICHIGAN, ASSIGNORS TO CLARK TRUCTBACTOR COMPANY, OF BUCHANAN, MICHI- GAN, A CORPORATION OF MICHIGAN.

PORTABLE ELEVATING APPARATUS.

Application filed May 8,

This invention relates to improvements in portable elevating devices adapted for use in connection with the lifting, transporting and stacking of articles of various kinds, in and around shops, factories, railway stations and other places, such mechanism being connected with a motor vehicle of the type known as a shop tractor. More particularly it relates to a lifting and transporting apparatus adapted to be direc ly connected with and carried by a wheeled frame of the general character of that shown and described in our pending applicatlon Serial No. 683,719, filed on December 31, 1923, which frame partially embraces the tractor-frame and is removably attached thereto. The leading object of the invention is to provide a lifting mechanism of strong; and durable construction adapted for the lifting and transporting of loads of very considerable weight, and so constructed that the verticallymoving load-sustaining member may be moved either up or down smoothly and easily without liability of any binding or sticking, and at all times be under perfect control of the operator of the tractor. This object we attain by theconstruction and arrangement of parts as shown in the drawings and hereinafter particularly described. :VVhat is believed to be new will be set forth in the claims.

In the drawings- Fig. 1 is a view in side elevation of an apparatus embodying the invention;

Fig. 2 is an enlarged vertical section taken substantially on the line 2-2 of Fig. 1;

Fig. 8 is a section taken substantially on the line 3-3 of Fig. 2;

Fig. 4 is an enlarged View partly in plan and partly in horizontal section, some parts being broken away;

Fig. 5 is a front view,portions of the apparatus being partly broken away, and one of the differential sheaves and its shaft being in section;

6 is a detail being a vertical section taken. on the line 6 -6 of Fig. 5; and

Fig. 7 is a cross-section through the loadsupporting platform, the sectionbeing taken at line 77 of Fig. 4.

Referring to the several figures of the drawings,10 indicates the main frame of a motor veh'cle of the type employing an internal combustion engine as the motive ing which encloses the motor and other operating parts. The details of the tractor con struction need not be here entered into as in and by themselves they form no part of the present invention, and, indeed, may vary widely in construction and arrangement. However, attention is called to the fact that projecting through one side of the casing is a power take-off shaft 11 which'is adapted to be driven from the engineand upon the projecting end of such shaft is secured a pulley 12 from which power is taken, as hereinafter described, for controlling the movements of the lifting mechanism. The tractor shown has two supporting wheels at its rear end, the one shown in Fig. 1 being indicated by 13, and the axle on which said wheels are mounted being driven from the engine as usual. The single supporting wheel at the forward end of the main frame 10 is indicated by 14, and this wheel is controlled for steering purposes by means of a steering wheel 15 and a steering post 16, which latter may be operatively connected with said front wheel in any usual manner.

14 l'emental frame, the two approximatelyparallel arms of which are adapted to extend alongside of the side members of the tractor frame 10 and are detachably and pivotally secured to such frame 10 at points considerably in rear of the dirigible wheeled support of the tractor. While the sides of this frame 17 may be formed and connected as shown'in our said application Serial No. 683,719, so far as an embodiment of our present invention is concerned, yet preferably we employ spring devices 18 that areinterposed between the ends of the sides of the frame 17 and the point of pivotal attachment as set forth in another pending application filed by us on February 27, M24, as Serial No. 695,536. At opposite sides of the longitudinal center of the yolreshaped member 17 are provided wheeled supports each in the form of a caster wheel 19 mounted between the arms of a yoke 20 that is suitably journaled in the sleeve portion 21 of a bracket 22 that projects out from the front face of the yoke shaped member 17all substantially as shown in either 1. indicates a yoite-shaped member or slip of said two applications. At the forward end of the yoke-shaped member 17 there is provided a curved plate 23 which constitutes not only a gusset for stiffening purposes, but also furnishes means for attaching in place the rigid vertical guide mem bers of the lifting apparatus. As shown, (see Fig. l) this curved plate lies against the inner face of the supplemental yokeshaped frame 17 and conforms in shape to the curved forward portion thereof. This curved plate will be secured. preferably by riveting it, to the member 17. Riveted to the outer face of this curved plate 23 and extending forwardly therefrom are two brackets 24 each formed of a heavy piece of sheet metal, these plates 24: being spaced apart and lying at opposite sides of the longitudinal median line of the frame 17.

25, 25 indicate two vertical posts each formed, as best shown in Fig. 4, of a channel bar, these bars being so relatively arranged that their channels lie opposite each other. To the outer faces of these channel bar posts are respectively riveted the outer end portions of the plate-like brackets 24. At their upper ends these posts 2 1 are connected together, preferably by a tie rod 26, as shown, and are also connected, in the construction shown, by an angle iron brace 27 that extends between them at a short distance below their upper ends. Riveted to this brace 27 midway between the two posts 25 is a guide rail 28 which, in the construction shown, is in the form of a T-rail. The inner head of this guide rail lies against the face of the curved plate 23 that is'carried by the yoke-shaped frame 17, and it is to be riveted at intervals to such curved plate 23. Owing to the forward portion of the yoke-shaped member 17 lying in advance of the curved plate 28, as clearly shown in Fig. at, it is evident, of course, that the guide rail 28 cannot well be continued below the frame 17, but as it is necessary to have guiding means below that frame as well as above it, as hereinafter described, we pro vide a separate strip 29 (see Fig. 6), that is riveted to the plate 23, the outer face of which forms a continuation of the track formed by the outer head of the rail 28, and, as shown in said Fig. 6, this strip 29 is notched as at 30 so that the front portion of the yoke-shaped member 17 may project thereinto.

31 indicates the main or body portion of the vertically movable carriage, which, as shown, is provided with two rearwardlyprojecting arms 82 each projecting opposite the inner or channeled face of one of the guide posts 25. Through openings in these arms passes a shaft and upon each projecting end of such shaft is suitably mounted a large roller 34 of a size and shape to rotatably fit within the channel of one of the posts 25-the rollers lgieing preferably provided with flanges that lie against the edges of the channeled posts as shown in Fig. i. The posts thus act as guides for tho rcwpcctive rollers of the carriage, but in order to give further guiding support to the carriage there is provided another guide roller 35 whichti'avels upon the con 'ral guide rail 28 and its extension 29. This guide roller is mounted upon a shaft 36 that is supported between two rearwardly projecting brackets 37 carried by the lower portion of the main or body portion of the carriage All. This roller 35 is preferably flanged at its ends, as shown, so that the head of the rail 28 is received between such flanges, and, as the centrally-disposed roller 35 is located some little distance below the other two guide rollers it will be seen that by reason of this arrangement of the three point engagement afforded by the several rollers the carriage as awhole is adapted to be moved smoothly and without tendency to any doparture from a straight vert cal path.

Turning now to the means by which the arriage is caused to move up and down on its several guides, 38 indicates a rotatable shaft extending across the rear faces of the posts 25 and journaled in suitable bearings secured to said posts near the upper ends thereof. Upon each projecting end portion of said shaft is keyed a spiral gear 35), such spiral gears being located adjacent to the two posts 25, respectively. Each of these gears 39 is in mesh with another similar gear 40 that is keyed upon a short shaft 41, such shafts 41 extending at right angles to the shaft 38, and each of said shafts being mounted in bearing boxes 42 that are secured against the outer faces of the two posts, respectively, near the upper ends of such posts. As shown in Fig. 2, we preferably form with each bearing box a divided casing member for enclosing one of the sets of spiral gears 39 and 40-each of such casings being indicated generallv by On the forward end of each of the shafts 11 is keyed a differential sheave 44-, the two grooves of which are so shaped as to engage in a non-slipping manner with the links of a lifting chain as usual. The two chains that engage respectively with. the two differential sheaves 44 are indicated by 45, and, as shown, each chain depen its differential sheave down to and around another sheave 46. These last-named sheaves are secured to opposite end portions of the carriage body 31 through two laterally-extending arms 47, a7 (see Fig. i) which arms are preferably integral with the said member 31 and which, as shown, also extend slightly fartherforward than does the front edge of the main or body member 31 of the carriage. Each of these arms has. as best shown in Fig. 1, a r-earwardly projecting inc You

that the chain between such sheave 46 andits cooperating differential sheave will be positioned for perfect movement. A nut or nuts on the lower end of the stem of each yoke 49 serves to hold the yoke in place. These nuts permit anv initial adjustment to be made that may be found necessary due to slight variation in the length of the chains, and also to bring the body member 31 of the carriage to a level position from time to timein case such position is disturbed by the stretching or wearing of the chains from use. To effect the desired vertical movement of the head along its guides, means are provided for utilizing power from the engine. Such means comprise a gggroovedv pulley 51 suitably secured upon an end portion of the shaft 38 in close proximity to the casing that encloses one of the sets of spiral gears 89, 40, and over such pulley and engaging therewith is an endless chain 52 that leads down to and passes under a double grooved idler pulley 53 that is supported in a block or frame mounted near the forward end of the yoke shaped frame member 17, such chain 52 thence extending to and passing around the grooved pulley 12 that is fast on the shaft 11 driven from the engine as before stated.

In connection with the carriage member 31 there is shown load-supporting means which comprises a plurality of forwardlyoxtending fingers that are detachably connected with said carriage body member 31, and by reason of their ready detachability it is evident that in lieu of them other types of load-sustaining means might be connected with said carriage member. As here shown, the fingers referred. to comprise a central finger 54 and two other fingers 55, 55 located at some considerable distance from and at opposite sides of said central finger. Each of these forwardly-projecting lingers has an upturned vertical head, the head of the central finger being indicated by 54 and the heads of the other lingers being respectively indicated by 55*. The head 54 lies against the outer face of the carriage member 31, as clearly shown in Fig. 6, and the heads of the other lingers project up and lie against the rear faces of the lateral arms 47 of said carriage memberall of such heads being secured by bolts as shown. While, of course, the various fingers might be used advantageously in connection with some articles that were to be lifted and transported, yet, when the apparatus is used in connection with other articles it is desirable to provide a smooth platform for them to rest upon, and, therefore, there is shown in connection with such fingers a suitable platform 56 that rests upon said fingers and may be secured thereto in any suitable manner, and preferably having at its rear end an upturned flange 57 that bears against the front face of the head 54 of the central finger and against the front faces of the lateral arms 47, and which flange portion may, as indicated in Fig. 5, be separately riveted to the parts against which it lies, as well as being secured by the same bolts that secure the heads of the fingers to the JilllZS that they are in contact with. The platform is preferably provided along its margin with an angle iron protecting piece 58, and, best shown in Fig. 7, there is also provided a strengthening cross strip 59, which cross strip at the points of intersection with the fingers, is bowed downwardly, and beneath these bowed portions the end portions of the fingers are placed and secured by rivets. As indicated by dotted lines in Fig. 1, the upper surface of the forward portions of the fingers are inclined or bevelled so as to reduce their thickness where they pass under the bowed portions of the cross strip and while thus furnishing a very strong construction that tends to maintain the platform in the desired level condition, yet permits such platform to lie very close to the floor from which goods are to be taken or to which they are to be removed.

By the construction and arrangement of parts described, it will be evident that the load receiving platform "an be brought very close to the floor upon which the tractor runs, thus greatly facilitating placing of goods upon such platform or removing them therefrom, and by having the three guides, viz., the two side channcl-slniped posts 25 and the intermediate rail 28, and such intern'iediate rail being engaged by a guide roller located in a different horizontal plane from the two guide rollers at the side, the movement of the carriage will be in almost a perfectly vertical line, thereby avoiding any sticking or binding tendency of the moving parts. Furthermore, by the use of the differential sheaves at the upper ends of the guide posts 25 a powerful and even pull is had by the chains that respectively run over them and with no tendency to slippage of one chain which would rcsult in an uneven application of power. Also the crossconnection of these differential sheaves through the shafts and spiral gearing described insures an even and simultaneous application of powerto both of the said sheaves and the chains that are, respectively, in operative engagement with them, and thus, in addition to the described arrangement of the guide rollers, there is provided means that insure against any binding or sticking tendency of the carriage. As will be understood, the use of the differential sheaves makes it possible to stop the carriage in locked position at any point so that goods may be. easily, safely and conveniently stacked or removed from piles at any point or points within the limits of movement of the carriage.

A very considerable advantage is attained by securing the elevating mechanism as a whole to the supplemental yoke-shaped wheeled frame 1''? rather than directly to the tract-or frame itself, for, as pointed out in our said pending application No. 683,719, by carrying the load forward of the front end of said. member 17 the effect is that of a lever of the first class, in that the caster wheels of the member 17 correspond to the fulcrum of such a lever, and by reason of the two side bar members of the supplemental frame extending well back of the forward wheeled support of the tractor practically the entire weight of the tractor is made use of to counterbalance the weight of the load carried by the elevating mechanism. Therefore when the load is so counterbalanced the tractor can move freely and easily, and, owing to the close association of the member 17 with the frame of the tractor, the apparatus as a whole can be operated readily in comparatively close quarters. Furthermore, as the pulley 53 that the drive chain 52 passes around is mounted on said supplemental frame member 17, such supplemental frame can be permitted its necessary slight independent rising and falling movement, that is due to its caster wheels passing over irregularities in the surface of the floor, without any material disturbance or disarrangement of the said drive chain with respect to the other pulleys that it is in operative engagement with, as will be plain from an inspection of Fig. 1.

What we claim as our invention and de sire to secure by Letters Patent, is

1. In an apparatus of the class described, the combination of a shop tractor, vertical guiding means connected with said tractor opposite one end thereof, a load-sustaining member having means engaging with and movable along said guiding means, a rotatable shaft supported ny said guiding n'ieans, a differential sheave fixed upon said shaft, a chain passing'around and engaging said differential sheave and also connected with said load-sustaining member, and other means connected with said shaft and operable to rotate it in either direction.

2. In an apparatus of the class described, the combination of a shop tractor, two vertical spaced-apart guiding posts connected with said tractor opposite one end thereof,

two differential sheaves rotatably mounted. on said posts, respectively, a load-sustaining member, means on said member for cngaging with said guiding posts, two lifting chains rising from said load-sustaining member and respectively engaging with said differential sheaves, gear devices connecting said sheaves together to compel them to move in unison, and means for operating said gear devices.

3. In an apparatus of the class described, the ccmbii'iation of a shop tractor, two vertical spaced-apart guiding posts connected with said tractor opposite one end thereof, a rotatable shaft supported by each post, a differential sheave secured to each shaft, a gear fast on each of said shafts, a crossshaft supported by said posts, gears carried. by said cross-shaft and in mesh with said other gears, means for rotating said crossshaft in either direction, a movable loadsustaining member adapted to be guided by said guiding posts, and two chains each operatively connected with said load-sustaining member and with one of said differential sheaves.

4. In an apparatus of the class described, the combination of a shop ractor, a supplemental wheeled frame lying opposite the sides and one end of the tractor and adapted to have a limited rising and falling movement independent of the tractor, two vertical spaced-apart guiding posts carried by said supplen'iental frame atits forward end, a rotatable shaft supported by each post, a differential sheave secured to each shaft, a gear fast on each of said shafts, a crossshaft supported by said posts, gears carried by said cross-shaft said last-named gears being in mesh with said other gears, a pulley on said cross-shaft,-an idler pulley carried by said supplemental frame, a chain passing over said pulley and under said idler pulley, means connecting said chain with the engine of the tractor, a movable load-sustaining member adapted to be guided by said guiding posts, and two chains operatively connected with said load-sustaining member and with said differential sheaves respectively.

5. In an apparatus of the class described, the combination of a shop tractor, two vertical spaced-apart guiding devices connected with said tractor opposite one end thereof, another vertical guiding device supported between said first-mentioned guiding devices, a load-sustaining nember having means for separately engaging and moving along said three guiding devices, a lifting chain connected with said load-sustaining member, a differential sheave rotatably supported from one of said guiding devices, and over which sheave said chain passes, and means for rotating said sheave.

6. In an apparatus of the class described,

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the combination of a shop-tractor, two vertical spaced-apart guiding devices connected with said tractor opposite one end thereof, another vertical guiding device supported between said first-mentioned guiding devices, a load-sustaining member, means carried by said member for engaging and moving along said two first-n'ientioned guiding devices, other means carried by said member for engaging and moving along said intermediate guiding device, said last-named engaging means being in a different horizontal plane from the two first-named engaging means, a lifting-chain connected with said load-sustaining member, a difierential sheave rotatably supported from one of said vertical guiding devices and over which sheavesaid chain passes, and means for rotating said sheave.

7 In an apparatus of the class described, thecombination of a shop tractor, two vertical spaced-apart guiding posts connected with said tractor opposite one end thereof, a load-sustaining member having means en gaging with said guiding posts, two sheaves carried by said load-sustaining member near opposite sides thereof, a differential sheave mounted upon each of said posts, and two chains each operatively engaged with one of said differential sheaves and one of said other sheaves.

8. In an apparatus of the class described, the combination of a shop tractor, two vertical spaced-apart guiding posts connected with said tractor opposite one end thereof, a load-sustaining member having means engaging with said guiding posts, two sheaves carried by said load-sustaining member near opposite sides thereof, a differential sheave mounted upon each of said posts, means comprisinggear mechanism for connecting said two differential sheaves together, and two chains each operatively engaged with one of said differential sheaves and one of said other sheaves.

9. In an apparatus of the class described, the combination of a shop tractor, two vertical spaced-apart guiding posts connected with said tractor opposite one end thereof, a l0ad-sustaining member having means engaging with said guiding posts, two sheaves carried by said load-sustaining member near opposite sides thereof, a differential sheave mounted upon each of said posts, means comprising gear mechanism for connecting said two differential sheaves together, two

chains each operatively engaged with one of said differential sheaves and one of said other sheaves, and another chain connected with said means that connect said two differential sheaves together, and means for driving said last-named chain from the engine of the tractor.

10. In an apparatus of the class described, the combination of a shop tractor, two ver tical spaced-apart guiding posts connected with said tractor opposite one end thereof, a vertically-movable load-sustaining member having means engaging with said guiding posts, said load-sustaining member comprising a main or body portion and a plurality of projecting fingers detachably connected with said main or body portion, two sheaves carried by said load-sustaining member near opposite sides thereof, a differential sheave rotatably mounted upon each of said posts, and two chains each operatively engaged with one of said difierential sheaves and one of said other sheaves.

11. In an apparatus of the class described, the combination of a tractor, ver tical guiding means flexibly connected with said tractor opposite one end thereof to swing vertically relatively thereto, a wheeled support for said guiding means, a load sustaining member having means engaging with and movable along said guiding means, a rotatable shaft supported by said guiding means, a differential sheave fixed upon said shaft, a chain passing around and engaging said differential sheave and also connected with said load-sustaining member, and other means connected with said shaft and operable to rotate it in either direction.

12. In an apparatus of the class described, the combination of a tractor, two vertical spaced-apart guiding posts connected with said tractor opposite one end thereof, two differential sheaves rotatably mounted on said posts respectively, a load- Sustaining member engaging and movable along said guiding-posts, two lifting chains rising from saidload-sustaining member and respectively engagingwith said differential sheaves, and means for driving said sheaves in unison.

13. In an apparatus of the classdescribed, the combination with a tractor com prising a motor, and means operated thereby for propelling the tractor, of two vertical spaced-apart guiding posts connected with the tractor opposite one end thereof, two differential sheaves rotatably mounted on said posts respectively, a load-sustaining member engaging and movable along said guiding posts, two lifting chains rising from said load-sustaining member and respectively engaging with said differential sheaves, and means for driving said sheaves in unison from said motor.

14. In anapparatus of the class described, the combination of a tractor, two vertical spaced-apart guiding devices connected with said tractor opposite one end thereof, another vertical guiding device supported between said first--1nentioned guiding devices, all of said guiding devices being flexibly .connectedwith the tractor to swing vertically in unison relative to the tractor, a loadsustammg member having means for separately engaging and moving along said three guiding devices, a lifting chain connected with said load-sustaining member, a differential sheave rotatably supported from one of said guiding devices, over which sheave said chain passes, and means for rotating said sheave.

15. In an apparatus of the class de scribed, the combination with a tractor comprising a motor, and means actuated thereby for propelling the tractor, of vertical guiding means flexibly connected with the tractor opposite one end thereof to swing vertically, a load-sustaining member engaging with and movable along said guiding means, and means connected with said load-sustaining member and driven by said motor for moving said load-sustaining member vertically along said guiding means.

16. In an apparatus of the class described, the combination with a tractor comprising a motor, and means actuated by said motor for propelling the tractor, of two vertical guides spaced apart and connected with the tractor opposite one end thereof, differential sheaves rotatably mounted on said guides respectively, a load-sustaining member movable vertically along said guides, means actuated by said motor for driving said sheaves in unison, and hoisting means connected with said load-sustaining member and operated by said sheaves;

17. A hoisting attachment for tractors comprising a wheel supported frame, means for flexibly connecting said Wheel supported frame with the tractor opposite one end thereof, vertical guides carried by said frame, a load-sustaining member movable vertically along said guides, sheaves mounted on said guides, means connected with said sheaves and operable to rotate them in unison by power derived from said tractor, and hoisting means connected with the load-sustaining member and actuated by said sheaves.

18. A hoisting attachment for tractors comprising a wheel supported frame, means for flexibly and detachably connecting said frame with the tractor opposite one end thereof, vertical guides carried by said frame, a load-sustaining member movable vertically along said guides, sheaves mounted on said guides, means connected with said sheaves and operable to rotate them in unison by power derived from said. tractor, hoisting means connected with the load-sustaining member and actuated by said sheaves, an intermediate guide carried by said frame between said first-mentioned guides, and means carried by said load-sustaining member and engaging said intermediate guide.

19. A hoisting attachment for tractors comprising a wheel supported frame adapted to be flexibly connected to the tractor opposite one end thereof, a channeled vertical guide carried by said frame, a load-sustaining member having means engaging and movable along the channel of said guide, a second guide mounted on said frame parallel with said first-mentioned guide, means carried by said loadsustaining member engaging said second guide in a different horizontal plane from said first-mentioned guideengaging means and movable along the same, and means for moving said load-sustaining member vertically along said guides.

20. In an apparatus of the class described, the combination with a tractor, comprising a motor and means actuated by said motor for propelling the tractor, of a frame connected with said tractor opposite one end thereof, vertically disposed guides mounted on said frame, a load-sustaining member movable vertically along said guides, hoisting means connected with said load-sustaining member and supported by said guides, and means driven by said motor for actuating said hoisting means.

21. In an apparatus of the class described, the combination of a motor driven tractor comprising a power take-off sheave, vertically extending guide means connected with said tractor at one end thereof, a load sustaining member having means engaging with and movable along said guide means, elevating means for causing said load sustaining member to move up and down along said guide means, and power transmission means for actuating said elevating means comprising an endless chain looped around the power take-oft sheave of said tractor.

22. In an apparatus of the class described, the combination of a motor driven tractor comprising a power take-off sheave adapted to be driven by the tractor motor, vertically extending guide means connected with said tractor at one end thereof, a wheeled sup.- port for said guide means, a load sustaining member having means engaging with and movable along said guide means, rotary winding devices supported on said guide means, flexible hoisting members extending from said load sustaining member oversaid rotary winding devices, and power transmission mechanism comprising a driven sheave operatively connected to said rotary winding devices, and an endless chain passing over said driven sheave and over the power take-oft sheave of said tractor.

23. In an apparatus of the class described, the combination of a motor driven tractorcomprising a power take-off shaft, vertically extending guide means connected with said tractor at one end thereof, a wheeled support for said guide means, a load sustaining member having means engaging with and movable along said guide means, rotary winding devices supported on said guide means adjacent the upper end thereof, flexible hoisting members extending from said load sustaining member over said rotary winding devices a shaft supported on said guide means ad ac-ent the upper end thereof, gear mechanism operatively connecting said shaft with each of said rotary win-ding devices, and power transmission mechanism operatively connecting said latter shaft with the power take-oil? shaft of said tractor.

2a. In an apparatus of the class described, the combination of a shop tractor comprising a power takeoff shaft, vertically extending guide means connected with said tractor opposite one end thereof, a load sustaining member having means engaging with and movable along said guide means, and hoisting means for said load sustaining member comprising a chain connected to said load sustaining member, and a differential sheave arranged to be driven from said power take off shaft and cooperating with said chain for operating said load sustaining member.

BERGER STOCKFLETH. FREDERICK W. BURGER. 

